When I tear-up enemy gyms, I always select my favourite pokemon as the initial defender. He has only 500-CP. Sure, he is defeated soon after, but that is ok. He is my buddy. I want him to have the glory. And, I have no clue about how to defend gyms... it seems to me that picking a high CP pokemon makes no difference and wastes potions.
So, can I make my low CP pokemon the lead defender of a friendly gym? If I battle with one of my 2000+CP pokemons and defeat everyone in a friendly gym, could I make my 500-CP the top defender? So everyone can (briefly) see him at the top? Or, is the order of defense only based on CP? Ignoring HP is ridiculous, but whatever. CP decides the order of defense?
11 Answer
The gym leader of the gym (or as you state, the lead defender) is decided only by CP. The strongest CP Pokemon is the gym leader. The order of Pokemon you battle in an opposing gym corresponds to ascending CP, starting with the lowest CP Pokemon and ending with the highest CP Pokemon, which is the gym leader.
Here's a relevant article that explains how to become a gym leader.
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